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x86/xen: use capabilities instead of fake cpuid values for aperf 

When running as pv domain xen_cpuid() is being used instead of
native_cpuid(). In xen_cpuid() the aperf/mperf feature is indicated
as not being present by special casing the related cpuid leaf.

Instead of delivering fake cpuid values clear the cpu capability bit
for aperf/mperf instead.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
This commit is contained in:
Juergen Gross 2017-04-12 08:27:07 +02:00
parent 3ee99df333
commit fd9145fd27
1 changed files with 1 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
arch/x86/xen/enlighten_pv.c
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@ -165,9 +165,6 @@ xen_running_on_version_or_later(unsigned int major, unsigned int minor)
return false;
}
#define CPUID_THERM_POWER_LEAF 6
#define APERFMPERF_PRESENT 0
static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0;
static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
@ -201,11 +198,6 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
*dx = cpuid_leaf5_edx_val;
return;
case CPUID_THERM_POWER_LEAF:
/* Disabling APERFMPERF for kernel usage */
maskecx = ~(1 << APERFMPERF_PRESENT);
break;
case 0xb:
/* Suppress extended topology stuff */
maskebx = 0;
@ -332,6 +324,7 @@ static void __init xen_init_capabilities(void)
setup_clear_cpu_cap(X86_BUG_SYSRET_SS_ATTRS);
setup_force_cpu_cap(X86_FEATURE_XENPV);
setup_clear_cpu_cap(X86_FEATURE_DCA);
setup_clear_cpu_cap(X86_FEATURE_APERFMPERF);
}
static void xen_set_debugreg(int reg, unsigned long val)